HYMENOPTERA. 377 



4. Trypoxylon ALBIPES. 



Female. Length 4i lines.— Black : the face covered ^vith 

 bright silvery pubescence ; the mandibles and palpi pale testa- 

 ceous ; the cheeks have a silvery pubescence. Thorax thinly 

 covered with a scattered silvery-white jnibescence, which is most 

 dense and glittering at the apex of the metathorax, on the pectus 

 and anterior coxae ; the mesothorax and scutellum smooth and 

 shining; at the base of the metathorax is an enclosed space, 

 which is coarsel}'^ reticulated and has a deep central channel ; on 

 each side of the enclosed space it is transversely sulcate ; wings 

 hy.iline and splendidly iridescent, the tegular pale testaceous ; 

 the base and extreme apex of the tibite pale rufo-testaceous; the 

 tarsi white, with the apical joints slightly ferruginous. Abdomen 

 elongate; the first two segments as long as the thorax, the basal 

 segment slender ; a fine silky short silvery-white pubescence 

 entirely covers the abdomen, very bright in certain lights, parti- 

 cularly on the sides. 



Hab. Albania. (Coll. W. W. Saunders, Esq.) 



5. Trypoxylon pileatum. 



Female. Length 4 lines. — Black : the clypeus covered Avith 

 silvery pubescence ; the face above the insertion of the antennae 

 produced into a shield-shaped form, rounded towards the vertex 

 and triangular in front ; from the lateral angles an acute edge 

 runs into the emargination of the eyes, on each side of which is 

 a smooth oblique plane. The mesothorax and scutellum smootli 

 and shining ; the metathorax enclosed at the base, the enclosure 

 with coarse divergent striae ; from the apex of the enclosure an 

 impressed channel runs downwards to the insertion of the abdo- 

 men ; on each side of the channel it is delicately transversely 

 striated and thinly covered with glittering silvery-white j)ubes- 

 cence ; the wings hyaline and beautifully iridescent. Abdomen 

 shining, the margins of the three basal segments slightly con- 

 stricted. 



Hab. Madras. (Walter Elliott, Esq.) 



6. Trypoxylon bicolor. B.M. 



Female. Length 7 lines. — Head and thorax black ; the head 

 thinlv covered with scattered cinereous jmbescence ; the face 

 with bright silvery pile ; the mandibles rufo-])iceous, the paljji 

 pale testaceous. Thorax tliinly covered with hoary pubescence ; 

 the metathorax above with a slightly hnpressed central channel. 

 subinterrui)ted at the verge of the oblique truncated poitiou, 

 beyond which it is much broader and more deeply impressed and 



